Since the inception of printed circuit boards in recent years, it has been necessary to provide supporting means therefor. Such supports preferably have means to permit removal and insertion of the printed boards because, among other reasons, when a circuit board fails, it may be quickly exchanged for a new or replacement board.
As electronic circuits have increased in complexity, the use of great numbers of circuit boards have been required and preferably are arranged in compact relationship to minimize space. This has lead to the development of various types of chassis to support said compact arrangements of circuit boards. Many of such chassis are sophisticated and are composed of parts requiring special dies to form not only end plates and rails or similar elements extending between said plates, but especially in the formation of grooved guide members which are used in opposite pairs respectively to slidably receive the opposite edges of the printed circuit boards which sometimes are referred to as cards.
Various types of chassis developed heretofore which require complex dies to form the same or which are time-consuming to assemble, and therefore, are expensive, are illustrated in the following exemplary U.S. Pat. Nos.: 3,640,399, Hartman, Feb. 8, 1972; 3,814,990, Warman et al, June 4, 1974; 4,013,928, Sarinopoulos et al, Mar. 22, 1977.
Additional prior United States patents pertaining particularly to types of grooved card guide members and means to support the same in the chassis are as follows U.S. Pat. Nos.: 3,016,148, Riddle, Jan. 9, 1962; 3,549,950, Shelden, Dec. 22, 1970.
Various means have also been developed heretofore to aid in the insertion of circuit boards into a chassis and removal of the same therefrom and the following U.S. Pat. Nos. illustrate exemplary devices and arrangements to effect the same: 2,976,510, Blain, Mar. 21, 1961; 3,476,258, Dorsett, Nov. 4, 1969.